1. Field of the Invention
The present invention relates to a vehicle occupant classification system that includes an optical pressure sensor. More specifically, the present invention relates to vehicle occupant classification system configured to determine the absence or presence of a passenger in a vehicle seat and classify the passenger in accordance with airbag deployment requirements.
2. Background Information
Various portions of vehicles are continuously being re-designed and modified to meet changes in safety standards. For example, in recent years airbags have been introduced to protect passengers in the event of an impact event. All airbags are operably connected to an airbag deployment system which typically includes a triggering device. The triggering device detects rapid changes in acceleration due to an impact event. Upon the detection of a potentially life threatening impact event, the triggering device sends a signal to the airbag deployment system instructing the system to deploy the airbag(s).
One recent development in airbag deployment systems is the inclusion of an occupant detection system that determines whether or not a passenger is seated in one of the vehicle seats. One such occupant detection system includes a pressure sensor that monitors the vehicle seat. When a passenger sits in the seat, the pressure sensor detects the mass of the passenger and sends a signal to the airbag deployment system. In response to receiving such a signal, the airbag deployment system arms the airbag such that during an impact event, the airbag deploys. If no passenger is present in the vehicle seat, the airbag does not get armed and the airbag does not deploy during an impact event.
One proposed development in airbag technology is an airbag with multiple levels of deployment. Such an airbag can be provided with two or more levels or stages of deployment, such as first deployment stage for a large passenger and a second deployment stage for a small passenger. A problem with such an airbag deployment configuration is that current airbag deployment systems and corresponding occupant detection systems are not provided with reliable means for categorizing the weight of passengers seated in a vehicle seat.
Further, current occupant detection systems are not able to distinguish between a passenger seated on a passenger seat and cargo resting on a passenger seat.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved occupant detection system for vehicle seats that can determine whether or not the load on a vehicle seat is a passenger or cargo, such as luggage or a bag of groceries, nor can such systems approximate the weight of a passenger(s) seated in a vehicle seat. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.